When a patient has a rapid heartbeat during pregnancy, the first step is to identify the cause of the abnormal heartbeat. It is recommended that the patient should be treated with oxygen and the cause should be further investigated, such as routine blood, serum ion and thyroid function tests and, if necessary, cardiac ultrasound and ambulatory electrocardiogram, to clarify the cause and assess the severity of the current fast heartbeat. If hypokalemia is diagnosed, it is recommended to eat foods with high potassium content, such as oranges, dates, bananas, potatoes and, if necessary, oral potassium chloride tablets. If it is caused by anemia, for example, iron deficiency anemia, then it can be combined with oral glucosamine.